Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.
Marginal VFR conditions (%)
Month
Average
2024
2023
2022
2021
2020
January
86.2
83
80
87
93
91
February
94.2
94
88
96
93
94
March
94.7
93
88
94
99
97
April
97.3
90
98
97
100
May
99.7
100
100
100
100
June
99.9
100
100
100
99
July
100.0
100
100
100
100
August
99.2
100
100
95
100
September
99.9
100
100
100
100
October
99.2
98
100
100
100
November
96.4
97
92
99
97
December
86.4
85
80
92
96
Average
95.6
89.8
93.9
96.1
97.4
97.9
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.
Maximum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
4.4
6
4
4
5
6
February
7.1
10
5
7
6
7
March
12.7
13
8
14
13
13
April
17.4
17
17
18
18
May
23.6
26
23
24
25
June
30.7
28
32
35
29
July
36.0
37
37
37
35
August
33.6
32
35
32
36
September
28.4
28
31
29
29
October
18.2
20
21
17
21
November
10.7
11
7
12
11
December
4.4
6
3
7
3
Average
17.8
9.1
18.5
19.7
19.5
19.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-3.2
-2
-2
-4
-4
-1
February
-2.7
1
-3
-4
-1
-3
March
2.9
3
1
3
2
4
April
6.0
5
5
5
7
May
11.4
14
10
11
13
June
16.9
16
17
20
15
July
22.6
23
24
23
21
August
20.4
21
22
19
22
September
15.0
16
17
15
14
October
6.4
8
8
7
7
November
1.2
2
-1
3
1
December
-3.3
-1
-3
-2
-5
Average
7.1
0.7
8.3
8.2
8.2
7.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.1
22
26
3
8
15
February
12.2
20
14
8
18
9
March
12.8
14
20
11
8
9
April
9.8
16
8
8
2
May
5.1
6
6
2
3
June
2.1
2
3
1
6
July
1.1
1
1
1
1
August
1.6
3
2
4
0
September
2.9
3
2
1
1
October
4.7
8
4
10
2
November
8.1
9
17
2
7
December
9.9
7
19
6
7
Average
8.1
18.6
9.3
6.5
5.4
4.8
Precipitation during daylight period
Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.
Wind speed (knots)
Month
Average
2024
2023
2022
2021
2020
January
6.0
6
7
5
6
6
February
8.2
8
8
7
7
7
March
8.9
11
9
10
9
9
April
8.3
9
8
8
8
May
7.9
8
8
8
8
June
8.3
8
8
8
8
July
7.8
8
10
7
7
August
7.2
7
7
8
7
September
7.8
9
7
7
7
October
7.1
6
7
8
7
November
6.1
5
7
6
7
December
6.0
5
7
9
6
Average
7.6
8.3
7.5
7.6
7.5
7.3
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
246°
232°
301°
177°
165°
February
187°
239°
288°
287°
282°
March
196°
195°
254°
218°
181°
April
270°
292°
324°
299°
May
208°
315°
308°
298°
June
222°
237°
216°
186°
July
166°
168°
181°
256°
August
159°
260°
196°
330°
September
171°
175°
312°
353°
October
262°
304°
168°
333°
November
303°
274°
309°
225°
December
300°
230°
178°
289°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.